The invention relates to a hull structure of nonmetallic material, in particular of a reinforced plastics material, for boats, ships, minesweepers and the like, which structure comprises a preferably one-piece shell and at least one deck and has a plurality of ribs which are distributed along the length of the hull and extend across the corresponding transverse section of said shell and a plurality of transverse members (known as beams) which extend directly underneath the deck.